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<p>Hi,</p>
<p>I noticed Windows exception handler is added to ecp_nistz256-x86_64.pl. In function full_handler, when restore register contents, rbx is the first one with the smallest offset:</p>
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<span style="font-variant-ligatures: no-common-ligatures; color: #cd7923">3181 </span>
<span style="font-variant-ligatures: no-common-ligatures"> mov -8(%rax),%rbx</span></p>
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<span style="font-variant-ligatures: no-common-ligatures; color: #cd7923">3182 </span>
<span style="font-variant-ligatures: no-common-ligatures"> mov -16(%rax),%rbp</span></p>
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<div><font size="3">but when do push, </font>rbp<font size="3"> is always the first one push to the stack:</font><br>
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<span style="font-variant-ligatures: no-common-ligatures; color: #cd7923"> 497 </span>
<span style="font-variant-ligatures: no-common-ligatures">.Lmul_mont:</span></p>
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<span style="font-variant-ligatures: no-common-ligatures; color: #cd7923"> 498 </span>
<span style="font-variant-ligatures: no-common-ligatures"> push %rbp</span></p>
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<span style="font-variant-ligatures: no-common-ligatures; color: #cd7923"> 499 </span>
<span style="font-variant-ligatures: no-common-ligatures"> push %rbx</span></p>
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<p>That is, the contents of rbx is restored to rbp and the content of rbp is restored to rbx. I think it is probably a bug of the code.</p>
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<p>Jun</p>
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